Cumnor Hill is a hill in the civil parish of Cumnor, to the west of the city of Oxford in the English county of Oxfordshire. In 1974 it was transferred from Berkshire. It is also the name of the ribbon development between the original Cumnor village and Botley outside the ring road on the outskirts of Oxford.

The road up Cumnor Hill was the original route of the A420 between Oxford and Swindon, until the Cumnor Hill by-pass was built in the 1970s. The road is now unclassified.

At the top of Cumnor Hill is the hamlet of Chawley, where the Kimmeridge Clay is close to the surface. There were brickworks there until 1937.

Position: (grid reference SP476050)

Coordinates: 51°44′30″N 1°18′43″W / 51.74169°N 1.31201°W / 51.74169; -1.31201

Coordinates: 51°44′06″N 1°19′55″W / 51.735°N 1.332°W / 51.735; -1.332

Cumnor is a village and civil parish 3.5 miles (5.6 km) west of the centre of Oxford, England. The parish of Cumnor includes Cumnor Hill, (a ribbon development between Cumnor village and Botley), Chawley (at the top of Cumnor Hill), the Dean Court area on the edge of Botley and the outlying settlements of Chilswell, Farmoor and Swinford. The parish was part of Berkshire until the 1974 local government boundary changes transferred it to Oxfordshire.

The village is about 2 miles (3.2 km) southwest of Botley and its centre is west of the A420 road to Swindon.

Cumnor has two public houses, the Vine and the Bear and Ragged Staff. It also has a newsagent, a butcher, a hairdresser, a post office/greengrocery and a complementary health clinic. There are three churches: the Church of England parish church of Saint Michael in the centre of the village, Cumnor United Reformed Church in Leys Road and Living Stones Christian Fellowship that meets in the Primary School.